Solid waste and hazardous waste rotary kilns are core thermal equipment specifically designed for the harmless treatment, volume reduction, and resource utilization of solid and hazardous waste. They are widely used in industries such as environmental protection, chemicals, metallurgy, and pharmaceuticals. Their core function is to completely decompose organic pollutants in solid and hazardous waste through high-temperature incineration (typically 850-1200°C, with hazardous waste treatment requiring ≥1100°C). This decomposes organic pollutants (≥99.99% incineration efficiency) and converts toxic and hazardous components into harmless or easily handled materials. This also reduces the volume of ash and slag (reduction rates can reach 70%-90%). In some scenarios, waste heat can be recovered (e.g., for power generation and heating) or the molten slag can be recycled (e.g., for building materials manufacturing).
I. Operating Principle:
The solid waste/hazardous waste rotary kiln achieves safe waste treatment through a closed-loop process of "continuous feeding - high-temperature incineration - flue gas purification - ash disposal." The specific steps are as follows:
Feeding Phase: Depending on the waste form (solid/semi-solid/liquid), solid/hazardous waste is continuously fed into the kiln tail end (high end) of the rotating drum using appropriate feeding devices (such as screw feeders, plunger pumps, or spray guns). During the feeding process, an air lock prevents flue gas leakage.
Preheating and Incineration Phase: As the kiln rotates, the material slowly moves along the inclined drum toward the kiln head end (low end) (at a speed of 0.3-1m/h). Simultaneously, the high-temperature flame (1000-1200°C) generated by the main burner at the kiln head and hot air flow from the kiln head to the kiln tail end:
Preheating Zone (kiln tail, temperature 400-800°C: Moisture (absorbed water and crystallized water) in the material evaporates, and low-boiling-point organic pollutants are initially volatilized.
Incineration Zone (inside the kiln, temperature 850-1200°C): Organic pollutants (such as benzene, phenols, and dioxin precursors) are completely decomposed into harmless gases such as CO₂ and H₂O. Some inorganic substances (such as heavy metals) are converted to molten or stable oxides.
Flue Gas Secondary Incineration: Flue gas from the kiln outlet (containing incompletely burned carbon particles and pollutants) enters the secondary combustion chamber. Under high temperatures of 1100-1200°C and turbulent mixing, it is incinerated again for ≥2 seconds to ensure the required destruction and removal rate.
Flue Gas Purification and Emission: The high-temperature flue gas (800-900°C) at the secondary combustion chamber outlet first enters a quench tower for rapid cooling (to inhibit dioxin regeneration), then passes through a bag filter to remove dust, a deacidification tower to remove acid gases, and a denitrification unit to remove nitrates. NOx is removed, and the final purified flue gas is discharged through the chimney (online monitoring of particulate matter, SO₂, NOx, dioxins, and other indicators is required).
Ash Disposal: The incineration ash (or molten slag) discharged from the kiln head is cooled by a cooling system and then disposed of in a classified manner:
Ordinary solid waste ash: After testing and meeting standards, it is landfilled or used to make building materials (such as unburned bricks);
Hazardous waste ash (such as those containing heavy metals): After further solidification and stabilization, it is sent to a hazardous waste landfill for disposal.
II. Core Performance Features:
Strong Adaptability: Compatible with Multi-Form Waste Treatment
Equipped with a multi-media feed system, it can simultaneously or separately process solid (such as waste plastics and rubber), semi-solid (such as chemical sludge and waste resin), and liquid (such as waste solvents and waste oil) hazardous waste/solid waste, eliminating the need for frequent equipment changes and adapting to the waste disposal needs of different industries (such as mixed hazardous waste from chemical companies, medical waste, and hazardous electronic waste).
High Safety: Complete Pollutant Decomposition
The dual-stage incineration design of "rotary kiln + secondary combustion chamber" ensures flue gas remains at a temperature of ≥1100°C for ≥2 seconds, achieving a decomposition rate of ≥99.99% for highly toxic substances such as dioxins, in compliance with the "GB 18484-2020 Hazardous Waste Incineration Pollution Control Standard."
The sealing system utilizes "mechanical seals + nitrogen protection" to prevent toxic gas leakage, and the odor concentration in the operation area is ≤0.001 mg/m³ (calculated as benzene).
Environmentally Compliant: Full-Process Pollution Control
The integrated flue gas purification system of "quenching + deacidification + dust removal + denitrification" controls particulate matter to ≤10 mg/m³, SO₂ ≤50 mg/m³, and NOx ≤200 mg/m³. A CEMS (Chemical Emission Monitoring System) is required to upload real-time data, ensuring transparent and traceable emissions. Ash disposal adheres to the principle of "classified management" to avoid secondary pollution.
Resource Utilization Potential: Waste Heat and Slag Recovery
Waste Heat Utilization: High-temperature flue gas (800-1000°C) generated by incineration can be used in waste heat boilers to generate steam, driving steam turbines for power generation or providing heating for the plant and surrounding areas. Approximately 0.3-0.8 MW·h of waste heat can be recovered per ton of waste.
Slag Resource Utilization: Partially molten slag (such as hazardous metallurgical waste slag that does not contain heavy metals) can be cooled and made into building materials such as glass-ceramics and permeable bricks, effectively turning waste into treasure.
Stable and Reliable: Adaptable to Complex Operating Conditions
The drive system utilizes variable frequency speed regulation, adjusting the kiln speed and burner load based on the calorific value of the waste (such as high-calorific-value waste plastics and low-calorific-value sludge) to avoid flameout or overburning. The lining bricks are made of acid-resistant and wear-resistant materials, with a service life of 1-2 years. The equipment's annual operating rate is ≥80%, meeting continuous disposal requirements.
III. Application Areas
Hazardous Waste Disposal: Treatment of hazardous chemical waste (such as waste solvents and catalysts), medical waste (such as infectious waste and pathological waste), electronic waste (such as waste circuit boards and batteries), and metallurgical waste (such as waste residues containing heavy metals) to achieve harmless treatment.
Solid Waste Reduction: Treatment of municipal solid waste (especially difficult-to-degrade components such as plastics and rubber) and industrial solid waste (such as waste plastics and tires) to reduce landfill volume.
Resource Utilization: Incineration of high-calorific-value solid waste (such as waste plastics and waste oil) to recover waste heat for power generation; Processing of heavy-metal-free molten slag (such as glass and ceramic slag) to produce building materials.
Emergency Disposal: Responding to sudden environmental incidents (such as hazardous waste leaks and expired chemicals) to quickly and safely destroy hazardous materials and prevent the spread of contamination.
Solid Waste and Hazardous Waste Rotary Kiln Equipment Parameters:
Specifications (m) | Processing capacity (10,000 tons per year) | Slope (%) | Equipment speed (r/min) | Motor power (KW) | |
φ2.2X11 | 1 | 2 | 0.1-2.2 | 22 | |
φ2.6X13 | 1.5 | 2 | 0.1-2.2 | 30 | |
φ2.8X16 | 2.5 | 2 | 0.1-2.2 | 37 | |
φ3.0X18 | 4 | 2 | 0.1-2.2 | 55 |